The present invention relates to apparatus and methods of supporting and shielding flexible outer bags of vacuum cleaners.
Vacuum cleaners are a pervasive and well-established appliance for commercial and residential floor care. A wide variety of vacuum cleaner configurations are available to suit the needs of a particular application or user, including upright vacuums, canister models, and hand-held models. A common element in many vacuum cleaner configurations is a flexible outer bag.
A prior art vacuum cleaner 20 with a flexible outer bag 22 is shown in FIG. 1. In this embodiment, the outer bag 22 includes a bag body 23 that has an enclosed end 24 and an openable end 25 that leads to an interior region (not shown) of the bag 20. In operation, dust and particulates are collected by a vacuum head 28 from a floor surface and are propelled by a flow of air into the interior region.
FIG. 2 shows another flexible outer bag 30 having an enclosed top edge 34, enclosed lateral edges 36A, 36B, and an openable front panel 35 that provides access to an interior region 35. A support means 32 supports the top edge 34, and small portions of the lateral edges 36A, 36B, of the flexible outer bag 30. The support means 32 includes a frame 33, which is attached to a backing plate 38. The frame 33 projects vertically from the backing plate 38 to support the top edge 34 of the bag 30, and extends laterally to support the upper regions of the lateral edges 36A, 36B. The frame 33 thus supports only the top edge 34, and a small portion of each lateral edge 36A, 36B. Support means 32 of the type shown in FIG. 2 are described more fully in U.S. Pat. No. 5,390,392 issued to Thomas et al.
The backing plate 38 (typically constructed of cardboard) is attached to the flexible outer bag 30 and has an aperture 39 disposed therethrough. The aperture 39 is aligned with an opening 31 in the flexible outer bag 30. The backing plate 38 may be mounted over an exhaust port (not shown) that projects into the interior region 35. An inner bag 40 may then be mounted over the exhaust port to receive the dirty air and particulate from the vacuum head.
FIG. 3 shows another prior art flexible outer bag 60 having an enclosed top edge 62, enclosed lateral edges 63, and an openable front panel 65 that provides access to an interior region (not shown). A support means assembly 50 supports the top edge 62 and also partially surrounds and protects the top edge 62 and small portions of the lateral edges 63 of the flexible outer bag 60. Support means assemblies of the type shown in FIG. 3 are described more fully in U.S. Pat. No. 4,662,913 issued to Vermillion.
Although desirable results are achievable using prior art the support means (FIGS. 2 and 3), certain problems still exist with respect to support and protection of the flexible outer bag. For example, the flexible outer bag may deform and come into contact with the inner bag. Such contact may decrease the efficiency of the vacuum cleaner because the inner bag may not fill with dirt or particulate to its maximum capacity. The areas of contact between the flexible outer bag and the inner bag may also reduce the airflow, and thus, the filtering efficiency of the vacuum cleaner. In addition, the prior art support means do little to protect the inner bag from being bumped or struck during operation of the vacuum cleaner which may cause damage to the flexible outer bag or the inner bag.
The present invention is directed toward structures and methods of supporting and shielding flexible outer bags of vacuum cleaners. In one aspect, a support structure includes a backing plate adapted to be disposed within the flexible outer bag, and at least one support member attached to the backing plate and projecting away from the backing plate. The backing and support members are adapted to contact and extend proximate respective portions of the outer bag, providing three-dimensional support to the outer bag. Alternately, a plurality of airflow apertures may be disposed through the support structure. In further aspects, the support member may be a support wall, a plurality of support tabs having airflow gaps therebetween, or may include a frame member.
In another aspect, a shield structure includes a backing member adapted to be positioned proximate to and extend over at least a portion of a rear panel of an outer bag of a vacuum cleaner. First and second sidewall members are attached to and project away from the backing member, the first and second sidewall members being adapted to be positioned proximate to and extend over at least a portion of corresponding lateral side panels of the outer bag. Alternately, the shield structure may further include a top member attached to and projecting away from the backing member, the top member being adapted to be positioned proximate to and extend over at least a portion of a top panel of the outer bag. In a further aspect, a front shielding member may be attached to the shield structure, the front member being adapted to be positioned proximate to and extend over at least a portion of a front panel of the outer bag.